This program is unfortunately no longer in development, which is a real shame. It seems that UI scaling didn't make it into the program before development was put on pause. This is can make it quite a strain on the eyes on larger monitors, however I have discovered a workaround, at least on my browser (I am using Firefox.)
By zooming in on the page *before* opening the web app, the web app will inherit the browser's zoom setting. You can achieve this with ctrl + scrollwheel. This does not work after opening the app. Beware scaling too far, because then some UI elements will become inaccessible. I have found 200% to be a good size on my monitor (2560x1440).
Hope this helps people!